一种WC-Co/316Lγ射线屏蔽复合材料交替沉积制备方法  

Preparation method of WC-Co/316L γ-ray shielding composites by alternating deposition

作　　者：乔春光 王中华 李博川[1,2] 姜潮 QIAO ChunGuang;WANG ZhongHua;LI BoChuan;JIANG Chao(State Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle,Hunan University,Changsha 410082,China;College of Mechanical and Vehicle Engineering,Hunan University,Changsha 410082,China)

机构地区：[1]湖南大学整车先进设计制造技术全国重点实验室,长沙410082 [2]湖南大学机械与运载工程学院,长沙410082

出　　处：《中国科学：技术科学》2024年第5期881-897,共17页Scientia Sinica(Technologica)

基　　金：国家自然科学基金重点项目(批准号:52235005),国家自然科学基金青年基金(批准号:52205262)资助项目。

摘　　要：核工业场景中普遍存在具有极强穿透能力的γ射线,极易造成机器人等智能装备的电路系统故障失效.传统钨、铅等屏蔽材料无法兼顾可加工性、辐射屏蔽性能及结构力学性能,难以同时满足结构承载、屏蔽功能及经济性综合最优的设计目标.基于此,本文以316L不锈钢为基体,以WC-Co为功能-结构增强材料,采用定向能量沉积增材制造(DED-AM)技术提出了一种新的WC-Co/316L功能-结构一体化γ射线屏蔽复合材料交替沉积制备方法.首先,研究了WC-Co/316L,316L两种粉末交替沉积工艺,通过优化调控激光功率、扫描速度、粉末配比等工艺参数,制备出WC-Co/316L功能-结构一体化γ射线屏蔽复合材料;其次,对制备出的复合材料进行微观结构与宏观力学性能表征;最后,采用蒙特卡罗粒子输运模拟方法对厚度、WC-Co含量及沉积方式不同的WC-Co/316L复合材料γ射线屏蔽性能进行分析.结果表明,该复合材料的低能γ射线屏蔽率明显提升,且在材料成型过程中增加了形核率并使晶粒细化,显著提高了材料的拉伸强度.本研究可为功能-结构一体化γ射线屏蔽材料制备提供指导.γ-rays with strong penetrating ability are prevalent in the nuclear industry scenario,and they can easily cause a circuit system failure in intelligent equipment like robots.Traditional γ-shielding materials,such as tungsten,lead,and others,cannot simultaneously consider processability,radiation shielding performance,and structural and mechanical properties.However,simultaneously meeting the optimal design goals for structural bearing capacity,shielding function,and economy is challenging.Therefore,using 316L stainless steel as the matrix and WC-Co as a function-structure enhancement material,this paper proposes a new fabrication method for WC-Co/316L function-structure-integrated γ-ray shielding composites based on directional energy deposition-additive manufacturing technology.First,the alternating deposition process of WC-Co/316L and 316L powder is studied.Subsequently,WC-Co/316L function-structure-integrated γ-ray shielding composites are prepared by optimizing the laser power,scanning speed,and powder ratio.Further,the microstructure and macroscopic mechanical properties of the prepared composites are characterized.Finally,the γ-ray shielding properties of the WC-Co/316L composites with different thicknesses,WC-Co contents,and deposition methods are analyzed using Monte Carlo particle transport simulation.The results show that the low-energy γ-ray shielding rate of the composite is considerably improved.During the fabrication of WC-Co/316L composites,their nucleation rate is increased and grain is refined,substantially improving their tensile strength.This study can provide guidance for preparing function-structure-integrated γ-ray shielding materials.

关 键 词：增材制造 多层交替沉积 γ射线屏蔽 WC-Co/316L 

分 类 号：TB33[一般工业技术—材料科学与工程] TL816.2[核科学技术—核技术及应用]